We are conducting a randomized, double blind placebo controlled study of surgery with or without raloxifene, EvistaTM for the treatment of pain from endometriosis. We are also studying the comorbidities of endometriosis including psychiatric, autoimmune and other disease states. A selective estrogen receptor modulator, raloxifene could prevent the regrowth of endometriosis and return of pain in women with pelvic pain from endometriosis. At the first study surgery, all women have laser excision of endometriosis during a laparoscopy. Those with biopsy proven disease are randomized to study treatment. Throughout the study women monitor the presence and intensity of various types of pelvic pain, their menstrual cycle, and other symptoms. Possible effects of raloxifene on the menstrual cycle, lipids, bone density, and in altering mood, causing headaches or deep vein thrombosis are monitored. We have accrued 70 women. To date, we have examined the utility of MRI in diagnosing endometriosis and correlated histopathology with laparoscopic findings. Our analysis suggests that MRI has a low detection rate of biopsy proven lesions and in determining whether an individual woman may have endometriosis suggesting that MRI has limited utility in a cohort of women with pelvic pain. Only about 70% of endometriosis lesions are biopsy proven. In the next year, we are planning to look at the utility of serum and urine markers in diagnosing endometriosis and the utility of intraoperative Marcaine instilled under the diaphragm in decreasing post-operative pain and nausea. We are also analyzing a large detailed survey on endometriosis conducted by the Endometriosis Association.